Improvement in electric telegraphs



A. BAIN.

Dial Telegraph Patented March 24, 1863 Nv PETERS. FhuXc-Lilhogrnpher.wunm mn. u. c.

UNITED STATES PATENT OFFICEQ ALEXANDER BAIN, OF NEXV YORK, N. Y.,ASSIGNOR TO HIMSELF AND WM. H. ALLEN, 0F SAME PLACE.

IMPROVEMENT IN ELECTRIC TELEGRAPHS.

Specification forming paltof Letters Patent No. 37,993, dated March 24,1863.

To all whom it may concern:

Be it known that I, ALEXANDER BAIN, of the cityand Stateof New York,have invented, made, and applied to use a certain new and usefulImprovement in ElectricTelegraphs; and I do hereby declare the followingto be afull, clear, and exact description of my said lIlVGH' tion,reference being bad to the annexed drawings, making part of thisspecification, wherein- Figure l is a plan of my telegraph-instrument.Fig. 2 is a vertical section of the same. Fig. 3 is a plan with thedials removed; and FigsA and 5 represent the movable dial-rings.

Similar marks of reference denote the same parts.

My invention is adapted to ordinary telegraphic operations, butespecially available for field-telegraphs for army use, or to thetransmission of secret messages that can be understood only by thepersons sending and receiving the same, and although the otherinstruments in the electrical circuit may move, still the message atthem will be unintellt gible.

My invention consists, first, in a rotary finger-plate that makes andbreaks the electrical circuit, and by means of an electro-magnet givesmotion to a hand that indicates upon a dial the letters or signstransmitted; second, in movable indicating-dials that can bevaried inthe order of the lettering or figuring to suit the wishes of the partiessending and receiving communications, and by this means the message canonly be understood by the sender and receiver, who have correspondingdials, the other instruments in the circuit having dials differentlettered, the message is unintelligible at such intermediate stations.Thus my instrument becomes adapted to use as a secret telegraph.

In the drawings, a represents a circular case of suitable size, shape,and material, around the top edge of which is a circular recessreceiving the edge of the finger-plate b. This finger-plate has near theedge thereof holes or recesses corresponding in number to the letters ofthe alphabet, or to the characters to be transmitted 5 and projectingfrom the edge of the case a over the finger-plate is a fixed stop, 0,and upon the surface of the finger plate are letters or characterscontiguous to each finger-hole. The operator, placing the finger uponthe hole opposite to the character to be transmitted, rotates the saidplate until his finger comes to the stop 0, the act of doing whichcauses as many pulsations and pauses in the electrical current as theremay be characters or letters passing said stop in the revolution of thefinger-plate until said plate is stopped. These electric pulsations andpauses are produced by alternate conducting and non-conducting surfaceson the said finger-plate corresponding in number to the hole in theplate I).

I have shown the flange l with sections of hard rubber or other suitablenon-conducting material introduced, as at 2, and against this flange thepoint of the spring (Z rests. Said spring is connected with thebinding-screw c, that receives one of the wires in the electricalcircuit and the other wire is connected to the binding-screwy, and thewire from the helix of the magnet 9 also connects to this screwf. Theother end of said helix connects to the brass bed-plate of theinstrument at 3, from which bed the spring It extends to the under sideof the finger-plate I). By this arrangement the armature '2 is attractedtoward the electro-ma-gnet when the point of the spring d rests upon themetallic part of the flange 1, so that the electrical currentpassesthrough the parts but when that current is broken by the non-conductingmaterial 2 in said flange 1 the armature is drawn back by the spring 4.This spring at may be regulated in its tension by a cord to theturniug-rodo.

From the armature 1' an arm, 6, extends to a crotch in the propeller 7,that vibrates on the arbor S, and has at the ends of the arms pallets 9and 10, so shaped, as shown, that the crown-wheel l will be caused toprogress one-half of the space between the teeth or pins each vibrationof the armature, and the hand will be moved and held in position as thean mature is drawn toward the magnet, and again moved and held inposition when the armature is away from the magnet, and on the arbor ofthis wheel Z is a hand, a, that revolves over the dial m, the nonius ofwhich dial is on the radial line of the finger-hole next in the left ofthe stop 0. By extending the arm 6 above the armature to take the crutch7 near its arbor, a sufficient motion is given to the pallets, althoughbut a small movement takes place of the armature.

The dials are lettered and numbered as shown in Fig. 1, or they may belettered in any other desired order, care being taken that the letterson the dial m are in the reverse order to those around the finger-plated.

The action of this instrument is as follows: The finger-plate anddial-hand, standing at the nonius, as in Fig. 1, the operator places hisfinger in the hole of the finger-plate opposite the letter to be sent,and revolves said plate in the direction of the arrow, until his fingerreaches said stop 0. The pulsations and pauses of electricity by thismovement have caused all the instruments in the circuit to indicate onthe dial m by'the hand neach successive letter or sign that passes thestop 0 in the revolution of said plate d, and the stopping of said handopposite the given letter or sign. indicates the same to be the onetransmitted, and then the operator places his finger in the hole for thenext letter to be transmitted, and rotates the plate as before.

The instruments are all to be adjusted by bringing the nonius intoposition at the end of each word, if required, and the hand shouldalways stand at this point when not in action.

The movement of the-hand on the dial of the instrument at thetransmitting-station enables the operator to see whether the pulsationshave all been correctlymade in the electrical circuit.

A small lever, 19, on the fulcrum 12, kept back by a coiled springaround the arbor, enables the operator to set the hand a by vibratin gthe armature.

Any convenient code of signals or characters may be arranged for thedials of this instrument, and all the instruments in a given circuit areto have corresponding fixed dials. I have shown an arrow in the line ofsignals pointing inward, which, when brought around twice, indicatesthat figures are to be used, and the other arrow in the said line ofsignals pointing outward, when similarly indicated, shows that lettersare to be used.

The mode of using my instrument for a secret telegraph will beunderstood from the following: Metallic or other rings or dials are tobe provided, as seen in Figs. 4 and 5, one ring of a size to set uponthe finger-plate b and cover the letters thereof and the other ring of asize to set upon the dial m. These rings have projecting studs at q q,entering holes in the respective dials at the nonius points 13. Theserings or dials may be covered with paper and letters, figures, or othercharacters written thereon on one or both sides, and movable rings thusprepared may be furnished to parties desiring to correspond, and theymay letter them at the particular divisions to suit their ownconvenience, and parties communicating may have any desired number ofthese rings or dials made in pairs, but the order of theletterin gvaried in each pair. These rings or dials being numbered or otherwisemarked and in the possession of parties desiring to correspond, theparticular rings are designated and placed on the instrument atzthe twostations, and the parties communicate intelligently to each other, andalthough all the other instruments may be connected so as to movecorrespondingly, the message can only be read by the two parties havingthe rings with lettering corresponding. I have illustrated this in thetelegraphic circuit surrounding the drawing, where the dials colored.red may correspond in the lettering to the rings, Fig. 4, those coloredyellow to the rings, Fig. 5, and those colored blue to the dials,Fig. 1. From this it will be seen that no message could be understood ifsent from a dial of one color except at the dial of the same color.

It will be evident that my system of movable rings or dials to form asecret telegraph might be used with any other character of telegraphicinstrument to which they may be applicable.

The rings or dials may be marked or lettered by engraving the same inthe metal, by painting, printing, or in any other convenient man ner,and the dials may be designated so as to know which is to be used bygiving the first two letters, thus, dial A B, dial N X, dial G D, &c.

What I claim, and desire to secure by Letters Patent, is-

1. The finger-plate provided with cavities or holes corresponding withthe sign to be transmitted, said plate in its revolution making andbreaking the electrical circuit, substantially as set forth.

2. The stop 0, in combination with the said fin ger-plate, for thepurposes and as specified.

3. The dial m and hand a, actuated substantially as shown, incombination with said finger-plate for receiving the message, asspecified.

4. The movable dials or rings applied to the transmitting andreceivinginstruments,whereby the telegraphic communication can only beunderstood by the sender and receiver, as set forth.

5. The fin ger-plate supported at or near its circumference, so that theinterior of said finger-plate may be open for exhibiting the dial m andhand it, as set forth.

In witness whereof I have hereunto set my signature this 31st day ofDecember, 1862.

ALEXR. BAIN.

Witnesses:

LEMUEL W. SERRELL, Guns. E. SMITH.

